Case escapement mechanism



June 25, 1957 R, Q TALBOT CASE ESCAPEMENT MECHANISM Filed June 5, 1953 IN VEN TOR. (1%? KWM United tent CASE ESCAPEMENT MECHANISM Richard C. Talbot, Joliet, 11]., assignor to J. L. Ferguson Company, Joliet, 111., a corporation of Illinois Application June 5, 1953, Serial N 0. 359,767

11 Claims. (Cl. 27144) This invention relates to a case escapement mechanism and it is an object of the invention to provide improved apparatus of this character.

The invention is particularly adapted to the'handling of cases, such as corrugated paperboard cases, which are to be employed for shipping packages, articles or produce. Empty cases are normally supplied infolded condition, that is, they are folded flat, and are inserted in the case magazine of a case filling machine in the same folded condition. Normally, the magazine of the filling machine is intended to maintain the empty folded cases in a vertical stack and to permit in seriatim withdrawal of the lowermost case. The withdrawn case may then be opened, its flaps closed and sealed at one end, the desired packages, articles or produce inserted, and the remaining flaps closed and sealed. One problem arising in such amachine is the seriatim withdrawal of one and only one case from the bottom of the supply stack without jamming and regardless of whether the cases are taped or stapled at their joints. Conventionally, one wall of the magazine or other fixed member extends downwardly to such a level with respect to the bed of the magazine that it engages and restrains from lateral movement all cases except the lowermost case. Accordingly, when movable fingers engage one edge of the lowermost case and attempt to withdraw it from the magazine, the above mentioned wall or fixed member permits the lowermost case to pass thereunder but restrains the next lowermost case and all superimposed cases from moving along with the lowermost case. Considerable difficulty has, however, been met with such arrangements, resulting usually from minute differences in the thicknesses of the folded cases and from the nature of the fold or crease at the advance edge of the cases. If the lowermost case is somewhat thicker than expected, the advance edge of the lowermost case may engage the lower edge of the above referred to wall and cause jamming. On the other hand, if the lowermost case is somewhat thinner than expected, the next lowermost case, which tends to be advanced with the lowermost case because of friction between the two cases, may nose under the restraining wall and become jammed. The same difiiculties may arise primarily from the fact that the advance folded edge of the cases are folded in such a way that the edge surface slopes in one direction or the other with respect to the vertical, all as described in detail below.

According to one embodiment of the present invention, the forward folded edge of the next lowermost case is engaged by a member which is serrated wherebyit may more securely engage and restrain the lowermost case from advancement, even though it may engage only the upper portion of the advance edge of that case. Accordingly, this member may be located somewhat higher than the conventional restraining means, whereby it ensures free pas-sage thereunder of the lowermost case and, at the same time, assures proper restraining of movement of the next lowermost case. Preferably, this serrated restraining means is arranged to withdraw from engagement with the next lowermost case after the lowermost case has been withdrawn from the stack. This assures that the advance edge of the new, lowermost case will not be hung up on the restraining means, this being a real possibility since the serrated restraining member may dig into the advance edge of the case during the withdrawal of the preceding case.

Accordingly, it is another object of the invention to pro vide improved restraining means for the next lowermost folded case of a stack of cases.

It is another object of the invention to provide serrated restraining means of the character described which assure proper positioning of the lowermost case of a stack following withdrawal of the preceding case.

Alternate use of taped and stapled cases creates a further problem, resulting from the fact that taped cases are of double thickness throughout, while stapled cases are basically of double thickness but are of triple thickness in the area of the overlapping joint which is required for stapling. Because of this triple thickness the restraining wall of a conventional mechanism must be sufliciently high to permit passage of three thicknesses of material thereunder. At the same time, it must serve to engage and restrain the advance edge of the next lowermost case even when the latter overlies only a double thickness of material in the lowermost case. It will be apparent that this difficulty tends toward jamming of the next lowermost case under the restraining wall.

According to one embodiment of the present invention the serrated restraining means is normally located at a height such that it readily engages the advance edge of the next lowermost case. The restraining means is arranged, however, such that it may float upwardly when the triple thickness of material of the lowermost case passes thereunder. More specifically, the engagement between the serrated restraining means and the advance edge of the next lowermost case is such that the upward swelling of the advance edge of the next lowermost case, caused by the passage thereunder of the triple thickness of the lowermost case, drives the restraining means upwardly.

Accordingly, it is another object of the invention to provide improved restraining means for the next lowermost case of a stack of cases, said restraining means remaining in fixed restraining relationship with that case 'as the case rides up and down as a result of the passage thereunder of a stapled lowermost case.

The invention, together with further objects and advantages thereof, will best be understood by reference to the following description taken in connection with the v accompanying drawing, and its scope will be pointed out in the appended claims. 1

In the drawing, in which like parts are designated by like reference numerals:

Figure 1 is an elevational view of apparatus illustrating one embodiment of the invention;

Fig. 2 is a top plan view of the apparatus shown in Fig. 1;

Fig. 3 is a partial elevational view of the same apparatus showing the apparatus restraining a next lowermost folded case during withdrawal of a lowermost case;

Fig. 4 is a View similar to Fig. 3 but illustrating the restraining apparatus in withdrawn position;

Fig. 5 is a view similar to Fig. 3 but showing cases folded in a different manner; and

Fig. 6 is a view similar to Fig. 3 but showing the restraining apparatus in a raised position resulting from the withdrawal of a lowermost stapled case.

The embodiment of the invention shown in the drawing is intended to operate as a part of a completely automatic machine for withdrawing a single folded case from the flaps at one end of the case, filling the case, and, finally, gluing and closing the fiaps at the other end of the case. However, since the invention in this application is limited to the apparatus for restraining the next lowermost case during the withdrawal of the lowermost case, the disclosure is limited to the apparatus directly associated with this function.

In the lowermost left-hand corner of Fig. 1 there may be seen the forward or advance edges of a series of folded cases 10a, 10b and 10c resting upon a suitable base 11. It is intended that apparatus constituting part of the overall machine, but not disclosed in the drawings, is to engage the trailing or opposite edge of the lowermost case 10a and advance it to the right in Fig. 1, the case 10a sliding along the base 11. Since the case 1011 is the lowermost case of a substantial stack of folded cases contained in a suitable magazine, not disclosed in the drawings, there is substantial friction between the lowermost case 10a and the next lowermost case 10b. Accordingly, as the lowermost case 10a is withdrawn from the bottom of the stack, the next lowermost case 10b tends to be withdrawn also. For this reason it is necessary to provide means for restraining the next lowermost case from forward movement during the withdrawal of the lowermost case.

According to the present invention, such means are provided which engage the advance edge of the lowermost case 10b at least during the withdrawal of the lowermost case 10a. This restraining means consists of an assembly 12 which comprises, in the preferred embodiment of the invention, a pair of plates 13 secured as by rivets 14 to opposite sides of a spacer plate 15. As may be seen in Fig. 2, the plates 13 are serrated at their rearward edges, that is, the edges which are in position to engage the advance edge of the next lowermost case 10b. The serrated edge of the plate 13 is preferably sufiiciently sharp that if the case 10b tends to advance with any substantial force during the withdrawal of the case 10a, the serrated edge of the plate 13 will dig into the surface of the case 10b. The advantage of this arrangement is that the assembly 12 is thereby able to restrain advancement of the case 10b if any substantial engagement is provided between the restraining means and the case, and regardless of the nature of the fold at the advance edge of the case 10b.

This may best be understood by reference to Fig. 5 wherein it may be seen that the case b is folded in such a 'way that the abbreviated, substantially planar surface of the advance edge thereof slopes at a substantial angle with respect to the vertical. t will be readily understood that precise handling of corrugated paper is impossible since the corrugated cardboard may frequently vary substantially in its dimensions. For example, the lowermost case 10a in Fig. 5 may be irregularly folded at its advance edge whereby it is appreciably thicker than normal. For this reason it is necessary that the assembly 12 be raised above the bed 11 somewhat more than would be required to provide passage thereunder for a case 1011 of standard thickness. Conversely, the case 10a may have been compressed whereby it is appreciably thinner than normal, and under such circumstances the next lowermost case 10b may tend to jam under the assembly 12 during withdrawal of the next lowermost case 10a. More specifically, restraining means would engage the case 10b near the upper portion of the advance edge, and in the event that the case 10b happens to be folded as indicated in Fig. 5, there would be a substantial tendency for the case 10b to jam under the restraining means.

Where the restraining means is constructed in accordance with the invention as so far described, jamming of the cases is prevented by the fact that the serrated edge of one of the plates 13 (in this instance the lower plate) digs into the surface of the case 1012 after minute movement of the case to the right, whereupon the case becomes hung up on the restraining means. More specifically, it is held up so that it cannot jam under the restraining means. It has been found that the assembly 12 operates in this manner even though the case 10b is folded in the manner illustrated in Fig. 5 and even though the restraining means engages only the upper portion of the advance edge of the case.

The angular orientation of the plates 13 with respect to the bed 11 is also of considerable significance. It will be seen that the plates 13 are sloped in such a direction that after the case 10b has firmly engaged the serrated edge of either of the plates 13, any further minute advancement of the case 10b serves to elevate the advance edge of the case as the serrated edge of the engaged plate digs into the case. Accordingly, this feature of the inven tion further tends to avoid any jamming of the cases.

The assembly 12 is secured by any suitable means to the lower end of a vertical arm 16 which is pivotally secured by a pin 17 to a link 18. The latter is in turn pivotally mounted by a pin 19 on any fixed base 20, which may be a frame member of the case-handling machine, not shown in the drawing.

Also secured to the base 20 is an arm 21 which extends horizontally (downwardly in Fig. 2) to a point beneath the link 18. A screw 22 threadedly engages the arm 21 such that the free end of the screw may adjustably engage the bottom of the link. The screw thereby controls the normal height of the link 18, the vertical arm 16, and the case-retaining assembly 12. A lock nut 23 is provided, as shown in Fig. 1, to lock the screw 22 in adjusted position.

In Fig. 1 there may be seen a plate 25 which is secured to the vertical arm 16 by a pair of screws 26, the screws extending through respective spacers 27. The plate 25, in conjunction with the facing portion of 'the vertical arm 16, forms a slot for receiving a roller 30. The latter is rotatably mounted on a pair of arms 31 which are in turn pivotally mounted by a shaft 32 on a frame member or base 20a.

The shaft 32 is intended to be oscillated to swing the arms 31 between the position illustrated in solid lines in Fig. 1 and the position illustrated in phantom. When the arms 31 are in the position illustrated in solid lines, the roller 30 retains the vertical arm 16 in the position illustrated in solid lines, whereby the assembly 12 is locked in position to restrain the next lowermost case 10b in its proper position in the magazine. When the shaft 32 is rotated to its other extreme position, the arms 31 and the roller 30 assume the position illustrated in phantom in Fig. 1. In this case the roller 30, bearing against the plate 25 draws the vertical arm 16, and hence, the caseretaining assembly 12, to the position illustrated in phantom in Fig. 1.

The purpose in withdrawing the assembly 12 from engagement with the case 10b is to free the serrated plates 13 from the case 10b in the event that the serrations on one or both of the plates 13 may have dug into the advance edge of the case 10b. If, for example, withdrawal of the case 10a has caused the case 10b to advance minutely, the serrations on the plate 13 may have dug into the advance edge of the case 10b, whereupon, the advance edge of the latter case may be restrained from falling to the lowermost position against the bed 11 after withdrawal of the case 10a. Obviously, a subsequent attempt to withdraw the case 10b (now the lowermost case) will cause the case 10b to buckle and interrupt operation of the machine. As opposed to this, rotation of the shaft 32 to withdraw the assembly 12 from contact with the case 10b, as illustrated in Fig. 4, will assure the proper movement of the case 10b to the lowermost position. It will be noted that friction between the case 10b and the case immediately above will more than offset any minute tendency for the case 10b to follow the assembly 12 as the assembly swings to the right.

J m A.

- It is intended, of course, that the shaft 32 be oscillated in proper phase relationship with theoperation of the apparatus for withdrawing the lowermost case. More specifically, the shaft 32 is rotated to the left and, hence, maintains the case-retaining assembly 12 in case-retaining position during withdrawal of the lowermost case. After each withdrawal of a lowermost case and prior to the next withdrawal, the shaft 32 rotates to the right, thereby withdrawing the assembly 12 from contact with any cases and rotates again to the left whereby the assembly 12 returns to case-engaging position wherein it restrains the new, next lowermost case from advancement during the next Withdrawal of the lowermost case.

The mounting of the vertical arm 16 on the free end of the pivotable link 18 also permits the arm 16 and the case-retaining assembly 12 to move in a vertical direction as the link 18 pivots around the pin 19. This feature of the invention is of particular advantage when the'cases being handled are stapled rather than taped.

In Fig. 6 it will be seen that the partially withdrawn lowermost case 10a is stapled, whereby in the area of the stapled joint the folded case comprises three thicknesses of material. Normally this small area of triple thickness of material is located near the center of the folded case, :and hence near the center of the case-holding magazine. Preferably the bed 11 is dished out near the center of the magazine in order that both the forward and rearward edges of the lowermost case may bear firmly against the surface of the bed 11. Such an arrangement is disclosed :and claimed in application Serial No. 192,780, entitled Case Handling Apparatus, filed October 28, 1950, now Patent No. 2,750,856, June 19, 1956, by John L. Ferguson and Richard C. Talbot and assigned to the same assignee as the present invention.

It will be noted that as the stapled, triple thickness portion of the lowermost case 10a exits from the magazine, it necessarily raises the advance edge of the next lowermost case 10b, since the latter was previously resting upon the advance, double thickness edge portion of the lowermost case 10a. If the assembly 12 were retained rigidly in fixed position during the passage of the stapled portion of the lowermost case under the advance edge of the next lowermost case, the serrated plates 13 might lacerate the forward edge of the case 1021 and, in any event, would restrain rising of the case 10b whereby it would be difficult to force the lowermost case 10a out of the magazine.

By the expedient of h'angingthe vertical arm 16 from the free end of the link 18 it is provided that the assembly 12 may ride upwardly with the advance edge of the case 10b as the stapled portion of the 10a passes thereunder. It will be understood that the arm 16 and the assembly 12 are not caused to rise by power-driven apparatus but are driven upwardly by the upward swelling of the case 1015, the arm 16 and the assembly 12 merely riding with the case. When the stapled portion of the lowermost case 10a has passed to the right of the advance edge of the next lowermost case 10b, the latter case may again drop down to its original position wherein it is separated from the bed 11 by only a double thickness of material of the case 10a. The arm 16 and the assembly 12, of course, drop down with the case 10b to their original positions.

Preferably, the entire case-restraining apparatus described above is provided in duplicate in any one machine, whereby the next lowermost case is restrained at two spaced points along its advance edge rather than at a single point near the center of the advance edge. In such case the shaft 32 is preferably common to the two means whereby the two respective assemblies 12 may be withdrawn and returned to restraining position by a single power source.

It may now be seen that the novel apparatus described above and shown in the drawing provides for more definite restraining of the next lowermost casev of a stack of cases during withdrawal of the lowermost case than is provided by previously known apparatus. The plates 13,

wardly, and even though such engagement is limited to the uppermost portion of the advance edge of the case. In this connection it should be noted that the term serrated, as employed herein, is to be interpreted in the broadest sense since various forms of plate edges may perform the desired function satisfactorily and are equivalents of the specific embodiments illustrated in the drawing. The edges of the plates 13 might, for example, display a relatively small number of widely spaced points. It is preferred, however, that the plate edges be serrated or sawtoothed in the manner suggested in Fig. 2.

Reference has been made herein to the fact that the serrated edges of the plates 13 may dig into the advance edge of the next lowermost case if that case is forcibly urged forward during withdrawal of the lowermost case. In actual practice it has been found that the serrated edges of the plates do not pierce the outer sheet of material of a corrugated paperboard case but merely form indentations therein which do not in any Way weaken the case. Nevertheless, the slight penetration by the serrated plate edges, corresponding to the formation of such shallow indentations, is suflicient that the plates 13 may support the advance edge of the next lowermost case and prevent its wedging under the restraining means.

It will also be seen that the apparatus described above and shown in the drawing has the further feature of preventing the advance edge of the next lowermost case from becoming hung up on the restraining means as a result of any substantial penetration of the case by the restraining means. Still further, this apparatus is so arranged as to engage accurately the advance edge of the next lowermost case when it overlies a double thickness of material in the lowermost case, and to remain in the same engaging relationship when a triple thickness of material of the lowermost case passes under the advance edge of the next lowermost case. As a result of this particular feature of the invention, it is assured that there is effective restraining engagement between the restraining means and the next lowermost case at all times during the withdrawal of the lowermost case.

While a particular embodiment of the invention has been shown, it will be understood, of course, that the invention is not limited thereto since many modifications may be made, and it is, therefore, contemplated to cover by the appended claims any such modifications as fall within the true spirit and scope of the invention.

The invention having thus been described, what is claimed and desired to be secured by Letters Patent is:

1. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, case-engaging means having a thin serrated case-engaging edge for engaging and restraining one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, said serrated edge extending parallel to said edge of said next lowermost case.

' 2. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, case-engaging means having a thin serrated case-engaging edge, and means for supporting said case-engaging means in position to engage and restrain one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, said serrated edge extending parallel to and being sufficiently sharp to dig into said edge of said next lowermost case and thereby to restrain said case from wedging under said case-engaging means.

3. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, case-engaging means having a serrated case-engaging face, and means for supporting said case-engaging means in position to engage and restrain one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, said supporting means being arranged to permit raising and lowering of said case-engaging means in fixed engagement with said next lowermost case during withdrawal of said lowermost case.

4. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, case-engaging means having a serrated case-engaging face, means for supporting said case-engaging means in position to engage and restrain one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost-case of such stack, and means for withdrawing said case-engaging means from case-engaging position and for returning said case-engaging means to case-engaging position between withdrawals of lowermost cases, whereby the case in next lowermost position may drop freely to lowermost position.

5. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, case-engaging means having a serrated case-engaging face, means for supporting said caseengaging means in position to engage and restrain one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, and means for withdrawing said case-engaging means from case-engaging position and for returning said case-engaging means to case-engaging position between withdrawals of lowermost cases, whereby the case in next lowermost position may drop freely to lowermost position, said supporting means being arranged to permit raising and lowering of said case-engaging means in fixed engagement with said next lowermost case during withdrawal of said lowermost case.

6. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, a pair of spaced-apart case-engaging members having thin serrated case-engaging edges for engaging and restraining one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, said serrated edges extending parallel to said edge of said next lowermost case.

7. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, a pair of spaced-apart case-engaging members having thin serrated case-engaging edges, and means for supporting said case-engaging members in position to engage and restrain, one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, said serrated edges extending parallel to and being sufiiciently sharp to dig into said edge of said next lowermost case and thereby to restrain said case from wedging under said case-engaging means.

8. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, a pair of spaced-apart case-engaging members having serrated case-engaging faces, and means for supporting said case-engaging members in position to engage and restrain one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, said supporting means being arranged to permit raising and lowering of said case-engaging members in fixed engagement with said next lowermost case during withdrawal of said lowermost case.

9. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, a pair of spaced-apart case-engaging members having serrated case-engaging faces, means for supporting said ease-engaging members in position to engage and restrain one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, and means for withdrawing said case-engaging members from caseengaging position and for returning said case-engaging members to case-engaging position between withdrawals of lowermost cases, whereby the case in next lowermost position may drop freely to lowermost position.

10. In apparatus for retaining folded cases in a stack and for allowing seriatim withdrawal of only the lowermost case of the stack, a pair of spaced-apart case-engaging members having serrated case-engaging faces, means for supporting said case-engaging members in position to engage and restrain one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, and means for withdrawing said case-engaging members from ease-engaging position and for returning said case-engaging members to case-engaging position between withdrawals of lowermost cases, whereby the case in next lowermost position may drop freely to lowermost position, said supporting means being arranged to permit raising and lowering of said case-engaging members in fixed engagement with said next lowermost case during withdrawal of said lowermost case.

11. In apparatus for retaining horizontal folded cases in a vertical stack and for allowing seriatim withdrawal of only the lowermost case of the stack, substantially planar case-engaging means having a serrated case-engaging edge for restraining one edge of the next lowermost case of a stack of cases against lateral movement during lateral withdrawal of the lowermost case of such stack, said serrated edge extending parallel to said edge of said next lowermost case and said planar case engaging said means sloping upwardly away from said edge.

References Cited in the tile of this patent UNITED STATES PATENTS 1,433,873 Cogswell Oct. 31, 1922 1,634,074 Labombarde June 28, 1927 1,643,646 Swift Sept. 27, 1927 1,807,843 Hendrickson June 2, 1931 1,866,847 Finfrock July 12, 1932 2,378,306 Leonhart June 12, 1945 2,394,604 Ford Feb. 12, 1946 

